For contemporary aircraft, an avionics ‘platform’ consists of a variety of elements such as sensors, sensor data concentrators, a data communications network, radio frequency sensors and communication equipment, computational elements, effectors, and graphical displays. These components must share information with each other over the data communications network.
Legacy incarnations of these platform elements are in the form of individual subsystem elements often referred to as “federated systems”. A federated system is an application-specific subsystem in a self-contained package having its own dedicated logic, processors, and input/output interfaces. Multiple and separated federated systems rely on common subsets of data sources, but lack the sharing of processing resources and interfaces among federated systems.
Previous efforts to reduce the reliance on federated systems, resulted in the introduction of the ARINC 653 and ARINC 664 standards. ARINC 653 (A653) is an operating system in which each application, e.g., associated with a federated system function, is granted its own time slice partition and its own memory space partition in which to execute. This enabled what were multiple federated system functions to be hosted on a common processor and to share a common interface and wiring to an avionics data network based on ARINC 664 part 7 (A664p7).
In these systems, data is sampled, published, and transmitted at a higher frequency and an application executing in an ARINC 653 partition is run more frequently in order to ensure that the results produced by an application have sufficiently low input-data-sample-time-to-processed-output delay. Both the frequency of data publication rate and the frequency of application execution tend to be more frequent than would be necessary if data and its processing were synchronized.